Title :
Upgrading of silicon spheres using an airjet grinder [solar cell fabrication]
Author :
Levine, Jules D. ; Woodall, David K. ; Knepprath, Vernon E. ; Stevens, Gary D.
Author_Institution :
Texas Instrum. Inc., Dallas, TX, USA
Abstract :
The Spheral Solar technology involves upgrading of inexpensive metallurgical grade silicon by rounding chunks of raw feedstock material into spheres about 1 mm in diameter and then subjecting the spheres to sequential melt/removal cycles. In each melt/removal cycle, impurities are segregated to the surface of the sphere due to directional solidification and slagging, and then this surface layer is removed. An airjet grind removal method used to produce 10% efficient solar cells is described in this paper, together with structural information, supportive data and discussion regarding optimal removal strategies
Keywords :
directional solidification; elemental semiconductors; grinding; melting; silicon; solar cells; 10 percent; Si; airjet grinder; directional solidification; impurities; metallurgical grade silicon; optimal removal; raw feedstock material; removal method; rounding; semiconductor; sequential melt/removal cycles; slagging; solar cell fabrication; surface layer; upgrading; Abrasives; Building materials; Fabrication; Grinding machines; Impurities; Inorganic materials; Instruments; Photovoltaic cells; Raw materials; Silicon;
Conference_Titel :
Photovoltaic Specialists Conference, 1993., Conference Record of the Twenty Third IEEE
Conference_Location :
Louisville, KY
Print_ISBN :
0-7803-1220-1
DOI :
10.1109/PVSC.1993.347053
